jtolio / gls Goto Github PK

gls currently does not work at Go tip - it appears to have broken somewhere between 1.11.2 and golang/go@78c0e1f.

This means that the goconvey package doesn't work any more, since it relies on gls for context tracking.

Test code:

package main

import (
	"fmt"
	"runtime"

	"github.com/jtolds/gls"
)

func main() {
	fmt.Printf("Go version: %s\n", runtime.Version())
	manager := gls.NewContextManager()

	manager.SetValues(gls.Values{
		"foo": 1,
	}, func() {
		foo, ok := manager.GetValue("foo")
		fmt.Printf("foo, ok = %+v, %t\n", foo, ok)
	})
}

Output on recent versions:

Go version: go1.11.1
foo, ok = 1, true

Go version: go1.11.2
foo, ok = 1, true

Go version: devel +78c0e1f Fri Nov 9 19:57:57 2018 +0000
foo, ok = <nil>, false

For passing trace context, only current gls is not enough, is there a way to get parent goroutine id? So we can get parent trace context.

see for example smartystreets/goconvey#476
somebody said it's due to improved inlining (removing the tag frames from the call stack).

It request data from runtime stack every getValue, what about the loss in performance?
Thanks.

Hi @jtolds , glad to find these cool codes. I am the original creator and current PPMC, committer of Apache SkyWalking (incubating) project: https://github.com/apache/incubator-skywalking

I am a rookie and new for golang ecosystem, and aware of building an auto-instrument(I prefer most) is possible but hard. So the first step is providing a manual instrument sdk based on SkyWalking model, like you did in monkit-zipkin.

So I definitely look for the thread local propagation for matching our tracing context : https://github.com/apache/incubator-skywalking/blob/master/apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/context/ContextManager.java#L46 I assume the gls library can do that? Am I right?

And also, I found your spacemonkeygo/monkit library, but look like it is more likely based on a pure manual context propagation. Do I get the point right?

I hope you can have time to help with our Apache project.

Hey, I'm not sure if you're still interested in this library, but I was wondering if you could answer a question for me. My use case is similar to the second one mentioned in the read me. I'd like to find a way to identify an HTTP request context for metric purposes. Rather than passing around a context I'd like to consider a goroutine as the context so I can work out timing information on a per request basis.

Would your library work for this, or is it a bit of overkill since I'm really only interested in having an identifier for each goroutine (and possibly looking up the goroutine hierarchy to see if an ancestor is a known goroutine).

Hello,

Can you please tag and version this project?

I am the Debian Maintainer for gls and versioning would help Debian keep up with development.

For my Go interpreter gomacro, I had to use goroutine-local storage so I implemented https://github.com/cosmos72/gls - it uses a single line of assembler to retrieve a goroutine id.

Would you be interested in comparing the two implementations and perhaps add to each one the best features of the other?

A simple example below. GetValue should return 0, true, but in Go 1.12, it returns 0, false.

package main

import (
	"fmt"

	"github.com/jtolds/gls"
)

func main() {
	mgr := gls.NewContextManager()
	mgr.SetValues(gls.Values{"node": 1}, func() {
		fmt.Println(mgr.GetValue("node"))
	})
}

jtolds/gls cause gc stw increase:
sample code